Oil tight flange for shockproof x-ray units



April 6, 1937.

/ :LT/gf F. E. SACK OIL TIGHT FLANGE FOR SHOCKPROOF X-RAY UNITS Filed March 28, 1935 2 Sheets-Sheet l INVENTOR PU E'. 5246375.

B977 t? Qvl/ ATTORNE April 6, 1937. P. E. sAcKs 2,076,252

y OIL TIGHT FLANGE FOR SHOCKPROOF X-RAY UNITS Filed March 28, 1933 Sheets-Sheet 2 INVENTOR P/lz/L 5 SAC/f5.

BY j?? ATTORNE Patented Apr. 6, 1937 UNITED STATES PATENT OFFICE OIL TIGHT FLANGE FOR SHOCKPROOF X-RAY UNITS Application March 28,

7 Claims.

My invention relates to X-ray apparatus and particularly to shcckproof apparatus and X-ray tubes therefor wherein the danger of accidentally contacting any of the high voltage parts of the device is obviated.

Devices of this general type are known to the prior art in which the X-ray tube and the high potential source of energy therefor is encased Within a housing with both tube and transformer lo immersed in a body of insulating and cooling material having a higher di-electric strength than air, such as oil. By the utilization of a material having a higher dil-electric strength than air the spacing between all high tension carrying parts l5 is considerably lessened over that required for the same applied voltage when operating in air, thus resulting in an X-ray tube materially shortened in length due to a smaller spacing between the high tension electrode terminals.

Moreover, during operation of the device the X-ray tube generates appreciable heat which is dissipated by the envelope itself to the surrounding insulating and cooling `medium and in addition it may be more readily dissipated by providing the anode stem of the tube with a cooling radiator likewise immersed in this body. A

rugged and compact X-ray unit of a portable nature accordingly results which is free from the danger of electrical shocks to operator or pa- 5,0 tient and which is capable of supplying the X- ray tube with relatively high electrical energy.

In these devices, however, an objectionable feature is inherent due to the necessity for the X-rays radiating from the tube to penetrate the insulating and cooling medium surrounding the tube. The X-rays in passing through this medium are alfected to a great extent due to the oil or medium acting as a iilter thus materially altering the quality of the X-rays to which a patient or a sensitized lm is subjected.

My present invention constitutes an improvement in the X-ray tube support for shock proof apparatus as shown and described in the copending application of Montford Morrison, Se-

Li rial No. 654,654, led February 1, 1933 which has matured into Patent #1,968,051 dated July 31, 1934 in which all of the essential features requisite in shock proof X-ray apparatus are retained by preventing accidental shocks resulting to patient or operator through the immersion of all high tension terminals and carrying parts in a body of cooling and insulating material. Moreover, I utilize a fore-shortened tube due to the cooling and insulating material having a higher di-electric strength than air, but obviate the ob- 1933Se1'ial N0. 663,136

(Cl. Z50-34) jectionable feature of allowing the oil surrounding these high tension carrying parts to act as a lter for the X-rays emanating from the tube.

My X-ray tube is provided with a rigid support forming substantially a part of the tube thus rendering it readily adaptable to a shock proof apparatus by enabling the tube as a unit to be secured to the apparatus and form an oil tight seal therewith. By disposing the ray projecting portion of the envelope, through which the X-rays emanate from the anode target during energization of the tube, exteriorly of the casing or tank cncasing the high tension parts of the apparatus when the tube is secured thereto the quality of the X-rays is in no way affected by extrinsic obstacles.

For a better understanding of the novel features of my present invention reference may be had to the accompanying drawings wherein;

Figure 1 is a sectional View of a shock proof unit constructed in accordance with my invention `with a portion of the apparatus shown in diagrammatical form for the purpose of simplicity;

Figure 2 is an elevational View in section on an enlarged scale of the tube supporting structure shown in Figure 1 with a part broken away to better illustrate the several parts;

Figure 3 is an elevational view in section on a slightly enlarged scale of a modication of the tube supporting structure of Figure 1; and

Figure 4 is anelevational View in section on a slightly enlarged scale of still another modication of the tube supporting structure with a part broken away to better illustrate the several parts.

Referring now to the drawings in detail I have shown a casing '5 which may be of a light and durable metal suitably grounded as at 6. Ahigh tension transformer 'I diagrammatically illustrated having a primary winding 8 and a high tension secondary winding 9 is housed Within the casing and immersed in an insulating and cooling material, such as oil II. 'I'he primary winding 8 of the high tension transformer receives electrical energy from a suitable source of alternating current of the usual commercial potential (not shown) through a pair of conductors I2 and I3 passing through a suitable insulating block or terminal I4 provided in the wall of the casing.

An X-ray tube having a vitreous evacuated envelope I5, an anode I6 and a thermionic cathode I1, is secured to the casing 5 in a manner to be hereinafter more fully described, with the ray projecting portion of the envelope disposed eXteriorly of the casing and the remainder of the envelope disposed interiorly of the casing and immersed in a body of cooling and insulating material I I.

The anode I6 of the X-ray tube is provided with a cooling radiator I8 which is likewise immersed in the insulating and cooling medium for the purpose of transmitting the heat generated during operation of the tube to this latter medium and in addition the envelope I5 likewise dissipates appreciable heat to the surrounding medium.

The thermionic cathode I'l is adapted to receive heating current from a suitable source of low tension electrical energy, such as a transformer i9, which may be housed within the casing 5 or remotely disposed therefrom upon a suitable control stand which supports the unit contained within the casing 5. By disposing the low tension transformer exteriorly of the casing 5 the latter is materially reduced in weight.

The low tension cathode heating transformer is provided with a primary winding 2I and this winding is energized by means of a pair of conductors 22 and 23 which may be connected to the. same commercial source of supply as the conductors E2 and I3. A low tension secondary winding 24 of the transformer I9 supplies heating current tothe cathode I1 of the X-ray tube through a conductor 25 which extends to one of the cathode terminals 25 of the X-ray tube disposed exteriorly of the envelope and casing. The other end of the secondary winding 24 is connected to the grounded metallic casing 5 through a conductor` 2'I and as the remaining cathode terminal 23 is in metallic connection with the casing 5 a circuit to the cathode I1 is thus completed.

One end of the high tension secondary Winding 9 is connected to the anode terminal which constitutes the radiator I8, by means of a conductor Z9 disposed within the casing, and the remaining end of the high tension secondary Winding is connected through a conductor 3| to the grounded metallic casing 5 and is thus supplied to the cathode terminal 28 which, as before' stated, is in metallic connection with the casing 5.

In the operation of my shock proof unit a control stand is normally employed which contains the switches for connecting the primary winding 8 of the high tension transformer 1 and the primary winding 2i of the low tension heating transformer I9 to the commercial source of supply. The X-ray tube I5 is supported by the container 5 as shown in Figures 1 and 2 by means of a metallic flange 32 surrounding the envelope I5 and rigidly secured thereto, which may be composed of substantially the same metal as that of the casing 5. This flange may be secured to the casing 5 by any suitable means, such for example as studs 33 and nuts 34 with a gasket 35 interposed between the. iiange and the casing for the purpose of making an oil tight connection therebetween. Although` this flange 32 may be cast in one piece or otherwise formed I prefer, in the interest of economy of manufacture, to provide the same with an annular portion 36 which ts tightly within a groove 37 provided in the flange thus forming an integral member. The annular portion 33 is threaded internally as at 38 and a collar 33 having eXternalthreads 4I is arranged to engage the threaded portion 38 of the annular portion 3 6.

' The flange 32 is provided with a shoulder portion 42 extending slightly over the point of connection of the annular portion thereof. A plurality of oil resisting yieldable rings 43 are interposed between the shoulder portion 42 and the collar 39. A metallic ring 44 surrounds the envelope I5 of the X-ray tube and is in contact with the collar 39. This collar is provided with grooves 45 which may be engaged by a suitable tool for the purpose of rotating the same, thus forcing the metallic ring 44 against the oil resisting rings 43. The pressure thus exerted by the threaded engagement of the collar 39 with the annular portion 35 of the flange 32 compresses the oil resisting yieldable rings 43 and forces the latter in a radial direction into rm frictional engagement with the inner walls of the annular portion 35 and the envelope or" the X-ray tube I5. An oil tight connection is accordingly formed between the envelope and the ange which forms a rigid support for the entire X-ray tube with the flange constituting substantially a part of ther tube. The cathode terminal 26 to which the conductor 25 is connected is arranged to engage a spring clip or contact terminal 46 supported by an insulating block 4l with the latter in turn rigidly secured to the ange 32 thus completely insulating this spring clip and the cathode terminal 26 from the flange 32 and metallic i casing 5.

The cathode terminal 28 is likewise arranged to engage a similar spring clip contact terminal 48 but this latter terminal is rigidly connected to the flange member 32 and, as this latter is in metallic connection with the casing 5 by means of the studs 33 and nuts 34, an electrical connection is accordingly made. This transmits the high and low tension energy to the cathode terminal 28, as one side of the high voltage secondary winding and the low tension secondary winding is connected to the metallic easing 5, as before stated.

In addition to the oil resisting yieldable rings 43 I may, if desired, apply an oil resisting cement, such as @9, between the shoulder portion 42 of the angc 32 and the envelope I 5 of the X-ray tube and also between the collar 33 and the envelope I5, if desired, thus preventing any seepage of oil in the event the rings L33 become saturated. These rings 43, however, are composed of oil resisting composition which are not deleteriously affected afi-.cilong usage or contact with oil and accordingly an oil tight connection is always maintained between the ange member and the X-ray tube.

Referring now more particularly to Figure 3 I have shown the X-ray tube I5 supported by a similar ange 32 likewise provided with an annular portion 35 which ts within a groove 3l in the flange member 32 to form an integral unit in the same manner as described relative to Figures l and 2. In this particular modification I coat the envelope of the Zei-ray tube with a thin layer of metal 5l, such as copper or tin. This may be applied in any suitable manner so that the same adheres to the envelope.

In order to unite the X-ray tube with the supporting flange I fuse a still further metal 52 to the annular portion of the flange and the layer of metal 5i. This metal 53 naturally has a lower fusion temperature than either the metal 5I or the metallic ange 36 and must be applied with care, otherwise the heat in applying the metal 52 will cause the metal 5i 'to peel or otherwise become disengaged `from the envelope i5. In all other respects this modication is identical with Figures 1 and 2 and after the tube is provided with the flange it may be secured to the casing by an oil tight connection, as previously described. In Figure 4 I have shown still another method of constructing the X-ray tube support. Again I provide a flange member 32 together with an annular portion 35, but in this particular embodiment this annular portion is slightly tapered, as at 53. A plurality of oil resisting yieldable rings 43 are again interposed between the envelope and the annular flange portion as in Figures l and 2. In constructing the ange member of this modication I surround the annular portion 3E with a loose collar (not shown) having an internal diameter slightly greater than that of the largest portion of the annular' ange 36. By inverting the X-ray tube with the flange member surrounding the envelope thereof and the oil resisting rings 55 in the position shown in this gure, I then cast another collar 54 between the loose collar which constitutes a form or mold therefor and the annular ring portion 36. The molten metal accordingly flows into contact with the flange 32 and also between the envelope I5 and the annular portion 35 into contact with the oil resisting rings 43. This molten metal is sufficiently cooled after which the loose collar or mold may be removed. This accordingly forms an integral unit for supporting the envelope of the X-ray tube directly by the flange member 32.

Again I may apply an oil resisting cement 49 between the envelope I5 and the flange 52 to prevent any seepage of oil between the flange member and the X-ray tube. In this modication the flange with the X-ray tube supported thereby is secured to the casing 5 by a stud and nut connection in the same manner as described relative to the preceding modication.

Accordingly in all modifications shown the tube may be readily removed for replacement or repair without disturbing any other portions of the apparatus. In the type of X-ray tube shown the X-rays emanate from the bulbous end of the envelope adjacent the cathode, and by this particular construction the X-rays emanate from the tube during operation thereof exteriorly of the casing where it is entirely free from oil which would otherwise act as a lter for the X-rays and aifect the quality of the rays generated. The remainder of the envelope I5, together with the anode terminal and the cooling radiator I8, is disposed interiorly of the casing and thus immersed in the cooling and insulating material.

The heat generated during operation of the tube is transmitted to the cooling and insulating medium through the walls of the envelope, as well as by the radiator I8, resulting in effective cooling of the entire tube. Furthermore, all high tension parts carrying a potential above ground, such for example as the anode terminal or radiator I8, and the conductor 29 are immersed in the cooling and insulating medium having a higher di-electric strength than air. This enables the spacing between the electrode terminals and all high tension carrying parts to be considerably lessened for that required for the same applied voltage in air. Moreover, an X-ray tube considerably shortened in length results making a compact shockproof unit.

In View of the foregoing it becomes readily manifested that I have provided a shockproof unit that is rugged and compact in construction and in which the possibilities of accidental shocks resulting to patient or operator is entirely eliminated.

Although the greater portion of the X-ray tube when secured to the casing is immersed in the cooling and insulating medium the ray projecting portion of the envelope through which X- rays emanate is disposed exteriorly of the casing and medium, thus removing all obstacles which may in any Way affect the quality of the X-rays projected upon a patient or sensitized film.

Having described several embodiments of my invention I do not desire to be limited thereto as various other modifications of the same may be made without departing from the spirit and scope of the invention as set forth in the appended claims.

What is claimed is:

1. In an X-ray apparatus, the combination of a casing provided with a source of high potential electrical energy therein, an insulating and cooling medium enveloping said high potential source, an X-ray tube provided with an evacuated envelope having an anode and cathode therein and energizable by said high tension source, means surrounding the envelope of said tube and secured to said casing to form an oil tight seal therewith, means surrounding the envelope of said tube and engageable with said first mentioned means, and yieldable means interposed between both of said aforementioned means and adapted to be forced into frictional contact with the envelope of said tube and said first mentioned means to form an oil tight seal therewith by the engagement of said second mentioned means with said first mentioned means.

2. In an X-ray apparatus, the combination of a casing provided with a source of high potential electrical energy therein, an insulating and cooling medium enveloping said high potential source, an X-ray tube provided with an evacuated envelope having an anode and cathode therein and energizable by said high tension source, means secured to said casing forming an oil tight seal therewith and surrounding the envelope of said tube, for supporting the latter with the ray projecting portion of said envelope and cathode terminals thereof disposed exteriorly of said casing and the remainder of -said envelope and anode terminal disposed interiorly of said casing, means surrounding the envelope of said tube and engageable with said first mentioned means, and yieldable means interposed between both of said aforementioned means and operable to secure the envelope of said tube to said first mentioned means and form an oil tight seal therewith by compression of said yieldable means upon engagement of said second mentioned means with said first mentioned means.

3. In an X-ray apparatus, the combination of a casing provided with a source of high potential energy therein, an insulating and cooling medium enveloping said high potential source, an X-ray tube provided with an evacuated envelope having an anode and cathode therein and energizable by said high potential source, and means secured to the envelope of said tube for supporting the same from said casing with the ray projecting portion of said envelope disposed exteriorly of said casing and the remainder thereof disposed internally of said casing immersed in said insulating and cooling medium comprising a ange surrounding the envelope of said tube having an internally threaded annular portion and forming an oil tight seal with said casing, an externally threaded collar surrounding the envelope of said tube engageable with the threaded portion of said ange, and a plurality of oil resisting yieldable rings interposed between said flange and said collar, and adapted to be forced into frictional engagement with the envelope of said tube and said ilange to form an oil tight seal therewith upon the engagement of said collar with said flange.

4. In an X-ray apparatus, the combination of a casing provided with a source of high potential electrical energy therein, an insulating and cooling medium enveloping said high potential source, an X-ray tube provided with an evacuated envelope having an anode and cathode therein and energizable by said high tension source, a

flange surrounding the envelope of said tube and secured to said container by an oil tight connection for supporting said tube with the ray projecting portion of the envelope of said tube disposed eXteriorly of said container and the remainder of the envelope of said tube disposed interiorly of said container immersed in said insulating and cooling medium, said flange provided with an annular threaded portion and an annular shoulder, an externally threaded collar surrounding the envelope of said tube and engageable with the threaded portion of said ilange, and a plurality of oil resisting rings surrounding the envelope of said tube and interposed between the annular shoulder of said flange and said collar, said rings being pressed against the shoulder portion of said flange by the engagement of said collar with said ilange, and forced radially into frictional engagement with the latter and the envelope of said tube to form an oil tight connection between said tube and said flange.

5. In an X-ray apparatus, the combination of a casing provided with a source of high potential energy therein, an insulating and cooling medium enveloping said high potential source, an X-ray tube provided with an evacuated envelope having an anode and cathode therein and energizable by said high potential source, and means secured to the envelope of said tube for supporting the same from said casing with the ray projecting portion of said envelope disposed exteriorly of said casing and the remainder thereof disposed internally of said casing immersed in said insulating and cooling medium comprising a ilange surrounding the envelope of said tube having a tapering annular portion and forming an oil tight seal with said casing, a metallic collar cast around the envelope of said tube and the annular portion of said flange to unite the two and form a support for said tube, and means interposed between the envelope of said tube and said ange to prevent the ilow of molten metal through the annular portion of said ange during casting of said collar.

6. The combination with an electron discharge device having an evacuated vitreous envelope, of means for securing said device to a suitable support comprising an annular flange surrounding the envelope of said device, an annular collar surrounding said envelope and engageable with said annular ilange, and yieldable oil resisting means interposed between said annular collar and said iiange and adapted to be forced into rictional engagement with the envelope of said device and said ilange by the engagement of said collar with said iiange.

'1. An electron discharge device having an evacuated envelope provided with electrodes therein, an annular ange surrounding said tube and, means for securing said ange to said tube to form an oil tight seal, said means. comprising a metallic collar cast in molten state around the interior and exterior of said flange and around said tube, and an oil resisting material disposed between said flange and said tube to maintain the molten metal between said tube and flange until cooled and for preventing any seepage oi oil therebetween.

PAUL ERNEST SACKS. 

